CKQuery predicate fails with ANY-BEGINSWITH

Reading the CKQuery documentation, I found this example:

[NSPredicate predicateWithFormat:@"ANY favoriteColors BEGINSWITH %@", matchString]

If favoriteColors is a String List, that means that I can search for the beginning of each value in the string list, however if I tried this, the app crashes.

Terminating app due to uncaught exception 'CKException', reason: 'Invalid predicate: ANY nameSearch BEGINSWITH "Do"

In my test, nameSearch is a String List.

I don't know if I'm understand the documentation wrong and favoriteColors is not a string list, but then why they are using ANY?

Do you have a Searchable index on favoriteColors?

CKQuery predicate fails with ANY-BEGINSWITH
 
 
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